<%@ page contentType="text/html;charset=UTF-8" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<c:set var="ctx" value="${pageContext.request.contextPath}"/>
<%@ taglib prefix="shiro" uri="http://shiro.apache.org/tags" %>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
	<title>HTML5 GetUserMedia Demo</title>
	<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0" />
</head>
<body>
<input type="button" title="开启摄像头" value="开启摄像头" onclick="getMedia();" /><br />
<video height="120px" autoplay="autoplay"></video><hr />
<input type="button" title="拍照" value="拍照" onclick="getPhoto();" /><br />
<canvas id="canvas1" height="120px" ></canvas><hr />
<input type="button" title="视频" value="视频" onclick="getVedio();" /><br />
<canvas id="canvas2" height="120px"></canvas>

<script type="text/javascript">
	var video = document.querySelector('video');
	var audio, audioType;

	var canvas1 = document.getElementById('canvas1');
	var context1 = canvas1.getContext('2d');

	var canvas2 = document.getElementById('canvas2');
	var context2 = canvas2.getContext('2d');

	navigator.getUserMedia = navigator.getUserMedia || navigator.webkitGetUserMedia || navigator.mozGetUserMedia || navigator.msGetUserMedia;
	window.URL = window.URL || window.webkitURL || window.mozURL || window.msURL;

	var exArray = []; //存储设备源ID
	MediaStreamTrack.getSources(function (sourceInfos) {
		for (var i = 0; i != sourceInfos.length; ++i) {
			var sourceInfo = sourceInfos[i];
			//这里会遍历audio,video，所以要加以区分
			if (sourceInfo.kind === 'video') {
				exArray.push(sourceInfo.id);
			}
		}
	});

	function getMedia() {
		if (navigator.getUserMedia) {
			navigator.getUserMedia({
				'video': {
					'optional': [{
						'sourceId': exArray[1] //0为前置摄像头，1为后置
					}]
				},
				'audio':true
			}, successFunc, errorFunc);    //success是获取成功的回调函数
		}
		else {
			alert('Native device media streaming (getUserMedia) not supported in this browser.');
		}
	}

	function successFunc(stream) {
		//alert('Succeed to get media!');
		if (video.mozSrcObject !== undefined) {
			//Firefox中，video.mozSrcObject最初为null，而不是未定义的，我们可以靠这个来检测Firefox的支持
			video.mozSrcObject = stream;
		}
		else {
			video.src = window.URL && window.URL.createObjectURL(stream) || stream;
		}

		//video.play();

		// 音频
		audio = new Audio();
		audioType = getAudioType(audio);
		if (audioType) {
			audio.src = 'polaroid.' + audioType;
			audio.play();
		}
	}
	function errorFunc(e) {
		alert('Error！'+e);
	}


	// 将视频帧绘制到Canvas对象上,Canvas每60ms切换帧，形成肉眼视频效果
	function drawVideoAtCanvas(video,context) {
		window.setInterval(function () {
			context.drawImage(video, 0, 0,90,120);
		}, 60);
	}

	//获取音频格式
	function getAudioType(element) {
		if (element.canPlayType) {
			if (element.canPlayType('audio/mp4; codecs="mp4a.40.5"') !== '') {
				return ('aac');
			} else if (element.canPlayType('audio/ogg; codecs="vorbis"') !== '') {
				return ("ogg");
			}
		}
		return false;
	}

	// vedio播放时触发，绘制vedio帧图像到canvas
	//        video.addEventListener('play', function () {
	//            drawVideoAtCanvas(video, context2);
	//        }, false);

	//拍照
	function getPhoto() {
		context1.drawImage(video, 0, 0,90,120); //将video对象内指定的区域捕捉绘制到画布上指定的区域，实现拍照。
	}

	//视频
	function getVedio() {
		drawVideoAtCanvas(video, context2);
	}

</script>
</body>
</html>
